Merged devel-threads branch (r3066:3364) back into trunk

11 files changed, 281 insertions, 270 deletions

diff --git a/program/steps/mail/check_recent.inc b/program/steps/mail/check_recent.inc
index 9bc9e6f92..3c2827502 100644
--- a/program/steps/mail/check_recent.inc
+++ b/program/steps/mail/check_recent.inc
@@ -32,13 +32,12 @@ foreach ($a_mailboxes as $mbox_name) {
       }
       
       // get overall message count; allow caching because rcube_imap::recent_uids() did a refresh
-      $all_count = $IMAP->messagecount();
+      $all_count = $IMAP->messagecount(NULL, $IMAP->threading ? 'THREADS' : 'ALL');
       
       $unread_count = $IMAP->messagecount(NULL, 'UNSEEN', TRUE);
       $_SESSION['unseen_count'][$mbox_name] = $unread_count;
 
       $OUTPUT->set_env('messagecount', $all_count);
-      $OUTPUT->set_env('pagesize', $IMAP->page_size);
       $OUTPUT->set_env('pagecount', ceil($all_count/$IMAP->page_size));
       $OUTPUT->command('set_unread_count', $mbox_name, $unread_count, ($mbox_name == 'INBOX'));
       $OUTPUT->command('set_rowcount', rcmail_get_messagecount_text($all_count));
@@ -56,17 +55,27 @@ foreach ($a_mailboxes as $mbox_name) {
       if (empty($_GET['_list']))
         continue;
 
-      // use SEARCH/SORT to find recent messages
-      $search_str = 'UID '.min($recents).':'.max($recents);
-      if ($search_request)
-        $search_str .= ' '.$IMAP->search_string;
+      if ($IMAP->threading) {
+        $OUTPUT->command('message_list.clear');
+        $sort_col   = isset($_SESSION['sort_col'])   ? $_SESSION['sort_col']   : $CONFIG['message_sort_col'];
+        $sort_order = isset($_SESSION['sort_order']) ? $_SESSION['sort_order'] : $CONFIG['message_sort_order'];
+        $result_h = $IMAP->list_headers($mbox_name, NULL, $sort_col, $sort_order);
+        // add to the list
+        rcmail_js_message_list($result_h);
+      }
+      else {
+        // use SEARCH/SORT to find recent messages
+        $search_str = 'UID '.min($recents).':'.max($recents);
+        if ($search_request)
+          $search_str .= ' '.$IMAP->search_string;
 
-      if ($IMAP->search($mbox_name, $search_str, NULL, 'date')) {
-        // revert sort order
-        $order = $_SESSION['sort_col'] == 'date' && $_SESSION['sort_order'] == 'DESC' ? 'ASC' : 'DESC';
-        // get the headers and add them to the list
-        $result_h = $IMAP->list_headers($mbox_name, 1, 'date', $order);
-        rcmail_js_message_list($result_h, true, false);
+        if ($IMAP->search($mbox_name, $search_str, NULL, 'date')) {
+          // revert sort order
+          $order = $_SESSION['sort_col'] == 'date' && $_SESSION['sort_order'] == 'DESC' ? 'ASC' : 'DESC';
+          // get the headers and add them to the list
+          $result_h = $IMAP->list_headers($mbox_name, 1, 'date', $order);
+          rcmail_js_message_list($result_h, true, false);
+        }
       }
     }
     else {
diff --git a/program/steps/mail/func.inc b/program/steps/mail/func.inc
index 1968d20b2..5f52161c4 100644
--- a/program/steps/mail/func.inc
+++ b/program/steps/mail/func.inc
@@ -59,6 +59,17 @@ if (!isset($_SESSION['sort_col']))
 if (!isset($_SESSION['sort_order']))
   $_SESSION['sort_order'] = $CONFIG['message_sort_order'];
 
+// set threads mode
+$a_threading = $RCMAIL->config->get('message_threading', array());
+if (isset($_GET['_threads'])) {
+  if ($_GET['_threads'])
+    $a_threading[$_SESSION['mbox']] = true;
+  else
+    unset($a_threading[$_SESSION['mbox']]);
+  $RCMAIL->user->save_prefs(array('message_threading' => $a_threading));
+}
+$IMAP->set_threading($a_threading[$_SESSION['mbox']]);
+
 // set message set for search result
 if (!empty($_REQUEST['_search']) && isset($_SESSION['search'][$_REQUEST['_search']]))
   {
@@ -88,13 +99,20 @@ if (empty($RCMAIL->action) || $RCMAIL->action == 'list')
       $OUTPUT->set_env('search_mods', $search_mods);
       
       // make sure the message count is refreshed (for default view)
-      $IMAP->messagecount($mbox_name, 'ALL', true);
+      $IMAP->messagecount($mbox_name, $IMAP->threading ? 'THREADS' : 'ALL', true);
     }
 	
-  // set current mailbox in client environment
+  // set current mailbox and some other vars in client environment
   $OUTPUT->set_env('mailbox', $mbox_name);
+  $OUTPUT->set_env('pagesize', $IMAP->page_size);
   $OUTPUT->set_env('quota', $IMAP->get_capability('quota'));
   $OUTPUT->set_env('delimiter', $IMAP->get_hierarchy_delimiter());
+  $OUTPUT->set_env('threading', (bool) $IMAP->threading);
+  $OUTPUT->set_env('threads', $IMAP->threading
+	|| $IMAP->get_capability('thread=references')
+        || $IMAP->get_capability('thread=orderedsubject')
+        || $IMAP->get_capability('thread=refs')  
+  );
 
   if ($CONFIG['flag_for_deletion'])
     $OUTPUT->set_env('flag_for_deletion', true);
@@ -123,43 +141,26 @@ if (empty($RCMAIL->action) || $RCMAIL->action == 'list')
  * return the message list as HTML table
  */
 function rcmail_message_list($attrib)
-  {
-  global $IMAP, $CONFIG, $COMM_PATH, $OUTPUT;
-
-  $skin_path = $CONFIG['skin_path'];
-  $image_tag = '<img src="%s%s" alt="%s" />';
+{
+  global $IMAP, $CONFIG, $OUTPUT;
 
-  // check to see if we have some settings for sorting
-  $sort_col   = $_SESSION['sort_col'];
-  $sort_order = $_SESSION['sort_order'];
-  
   // add some labels to client
   $OUTPUT->add_label('from', 'to');
 
-  // get message headers
-  $a_headers = $IMAP->list_headers('', '', $sort_col, $sort_order);
-
   // add id to message list table if not specified
   if (!strlen($attrib['id']))
     $attrib['id'] = 'rcubemessagelist';
 
-  // allow the following attributes to be added to the <table> tag
-  $attrib_str = create_attrib_string($attrib, array('style', 'class', 'id', 'cellpadding', 'cellspacing', 'border', 'summary'));
-
-  $out = '<table' . $attrib_str . ">\n";
-
   // define list of cols to be displayed based on parameter or config
   if (empty($attrib['columns']))
       $a_show_cols = is_array($CONFIG['list_cols']) ? $CONFIG['list_cols'] : array('subject');
   else
       $a_show_cols = preg_split('/[\s,;]+/', strip_quotes($attrib['columns']));
 
-  // store column list in a session-variable
+  // save some variables for use in ajax list
   $_SESSION['list_columns'] = $a_show_cols;
+  $_SESSION['list_attrib'] = $attrib;
   
-  // define sortable columns
-  $a_sort_cols = array('subject', 'date', 'from', 'to', 'size');
-
   $mbox = $IMAP->get_mailbox_name();
   $delim = $IMAP->get_hierarchy_delimiter();
 
@@ -167,198 +168,19 @@ function rcmail_message_list($attrib)
   if ((strpos($mbox.$delim, $CONFIG['sent_mbox'].$delim)===0 || strpos($mbox.$delim, $CONFIG['drafts_mbox'].$delim)===0)
       && (($f = array_search('from', $a_show_cols)) !== false) && array_search('to', $a_show_cols) === false)
     $a_show_cols[$f] = 'to';
-  
-  // add col definition
-  $out .= '<colgroup>';
-  $out .= '<col class="icon" />';
-
-  foreach ($a_show_cols as $col)
-    $out .= ($col!='attachment') ? sprintf('<col class="%s" />', $col) : '<col class="icon" />';
 
-  $out .= "</colgroup>\n";
-
-  // add table title
-  $out .= "<thead><tr>\n<td class=\"icon\">&nbsp;</td>\n";
-
-  $javascript = '';
-  foreach ($a_show_cols as $col)
-    {
-    // get column name
-    switch ($col)
-      {
-      case 'flag':
-        $col_name = sprintf($image_tag, $skin_path, $attrib['unflaggedicon'], '');
-        break;
-      case 'attachment':
-        $col_name = sprintf($image_tag, $skin_path, $attrib['attachmenticon'], '');
-        break;
-      default:
-        $col_name = Q(rcube_label($col));
-    }
-
-    // make sort links
-    $sort = '';
-    if (in_array($col, $a_sort_cols))
-      {
-      // have buttons configured
-      if (!empty($attrib['sortdescbutton']) || !empty($attrib['sortascbutton']))
-        {
-        $sort = '&nbsp;&nbsp;';
-
-        // asc link
-        if (!empty($attrib['sortascbutton']))
-          {
-          $sort .= $OUTPUT->button(array(
-            'command' => 'sort',
-            'prop' => $col.'_ASC',
-            'image' => $attrib['sortascbutton'],
-            'align' => 'absmiddle',
-            'title' => 'sortasc'));
-          }       
-        
-        // desc link
-        if (!empty($attrib['sortdescbutton']))
-          {
-          $sort .= $OUTPUT->button(array(
-            'command' => 'sort',
-            'prop' => $col.'_DESC',
-            'image' => $attrib['sortdescbutton'],
-            'align' => 'absmiddle',
-            'title' => 'sortdesc'));
-          }
-        }
-      // just add a link tag to the header
-      else
-        {
-        $col_name = sprintf(
-          '<a href="./#sort" onclick="return %s.command(\'sort\',\'%s\',this)" title="%s">%s</a>',
-          JS_OBJECT_NAME,
-          $col,
-          rcube_label('sortby'),
-          $col_name);
-        }
-      }
-      
-    $sort_class = $col==$sort_col ? " sorted$sort_order" : '';
-
-    // put it all together
-    if ($col!='attachment')
-      $out .= '<td class="'.$col.$sort_class.'" id="rcm'.$col.'">' . "$col_name$sort</td>\n";
-    else    
-      $out .= '<td class="icon" id="rcm'.$col.'">' . "$col_name$sort</td>\n";
-    }
-
-  $out .= "</tr></thead>\n<tbody>\n";
-
-  // no messages in this mailbox
-  if (!sizeof($a_headers))
-    $OUTPUT->show_message('nomessagesfound', 'notice');
-
-  $a_js_message_arr = array();
-
-  // create row for each message
-  foreach ($a_headers as $i => $header)  //while (list($i, $header) = each($a_headers))
-    {
-    $message_icon = $attach_icon = $flagged_icon = '';
-    $js_row_arr = array();
-    $zebra_class = $i%2 ? ' even' : ' odd';
-
-    // set messag attributes to javascript array
-    if ($header->deleted)
-      $js_row_arr['deleted'] = true;
-    if (!$header->seen)
-      $js_row_arr['unread'] = true;
-    if ($header->answered)
-      $js_row_arr['replied'] = true;
-    if ($header->forwarded)
-      $js_row_arr['forwarded'] = true;
-    if ($header->flagged)
-      $js_row_arr['flagged'] = true;
-
-    // set message icon  
-    if ($attrib['deletedicon'] && $header->deleted)
-      $message_icon = $attrib['deletedicon'];
-    else if ($attrib['repliedicon'] && $header->answered)
-      {
-      if ($attrib['forwardedrepliedicon'] && $header->forwarded)
-        $message_icon = $attrib['forwardedrepliedicon'];
-      else
-        $message_icon = $attrib['repliedicon'];
-      }
-    else if ($attrib['forwardedicon'] && $header->forwarded)
-      $message_icon = $attrib['forwardedicon'];
-    else if ($attrib['unreadicon'] && !$header->seen)
-      $message_icon = $attrib['unreadicon'];
-    else if ($attrib['messageicon'])
-      $message_icon = $attrib['messageicon'];
-
-    if ($attrib['flaggedicon'] && $header->flagged)
-      $flagged_icon = $attrib['flaggedicon'];
-    else if ($attrib['unflaggedicon'] && !$header->flagged)
-      $flagged_icon = $attrib['unflaggedicon'];
-    
-    // set attachment icon
-    if ($attrib['attachmenticon'] && preg_match("/multipart\/m/i", $header->ctype))
-      $attach_icon = $attrib['attachmenticon'];
-        
-    $out .= sprintf('<tr id="rcmrow%d" class="message%s%s%s%s">'."\n",
-                    $header->uid,
-                    $header->seen ? '' : ' unread',
-                    $header->deleted ? ' deleted' : '',
-                    $header->flagged ? ' flagged' : '',
-                    $zebra_class);
-    
-    $out .= sprintf("<td class=\"icon\">%s</td>\n", $message_icon ? sprintf($image_tag, $skin_path, $message_icon, '') : '');
-
-    $IMAP->set_charset(!empty($header->charset) ? $header->charset : $CONFIG['default_charset']);
-  
-    // format each col
-    foreach ($a_show_cols as $col)
-      {
-      if (in_array($col, array('from', 'to', 'cc', 'replyto')))
-        $cont = Q(rcmail_address_string($header->$col, 3, false, $attrib['addicon']), 'show');
-      else if ($col=='subject')
-        {
-        $action = $mbox==$CONFIG['drafts_mbox'] ? 'compose' : 'show';
-        $uid_param = $mbox==$CONFIG['drafts_mbox'] ? '_draft_uid' : '_uid';
-        $cont = abbreviate_string(trim($IMAP->decode_header($header->$col)), 160);
-        if (empty($cont)) $cont = rcube_label('nosubject');
-        $cont = $OUTPUT->browser->ie ? Q($cont) : sprintf('<a href="%s" onclick="return rcube_event.cancel(event)">%s</a>', Q(rcmail_url($action, array($uid_param=>$header->uid, '_mbox'=>$mbox))), Q($cont));
-        }
-      else if ($col=='flag')
-        $cont = $flagged_icon ? sprintf($image_tag, $skin_path, $flagged_icon, '') : '';
-      else if ($col=='size')
-        $cont = show_bytes($header->$col);
-      else if ($col=='date')
-        $cont = format_date($header->date);
-      else
-        $cont = Q($header->$col);
-        
-      if ($col!='attachment')
-        $out .= '<td class="'.$col.'">' . $cont . "</td>\n";
-      else
-        $out .= sprintf("<td class=\"icon\">%s</td>\n", $attach_icon ? sprintf($image_tag, $skin_path, $attach_icon, '') : '&nbsp;');
-      }
-
-    $out .= "</tr>\n";
-    
-    if (sizeof($js_row_arr))
-      $a_js_message_arr[$header->uid] = $js_row_arr;
-    }
-  
-  // complete message table
-  $out .= "</tbody></table>\n";
-  
-  $message_count = $IMAP->messagecount();
+  $skin_path = $_SESSION['skin_path'] = $CONFIG['skin_path'];
+  $message_count = $IMAP->messagecount(NULL, $IMAP->threading ? 'THREADS' : 'ALL');
   
   // set client env
   $OUTPUT->add_gui_object('mailcontframe', 'mailcontframe');
   $OUTPUT->add_gui_object('messagelist', $attrib['id']);
+  $OUTPUT->set_env('autoexpand_threads', intval($CONFIG['autoexpand_threads']));
   $OUTPUT->set_env('messagecount', $message_count);
   $OUTPUT->set_env('current_page', $IMAP->list_page);
   $OUTPUT->set_env('pagecount', ceil($message_count/$IMAP->page_size));
-  $OUTPUT->set_env('sort_col', $sort_col);
-  $OUTPUT->set_env('sort_order', $sort_order);
+  $OUTPUT->set_env('sort_col', $_SESSION['sort_col']);
+  $OUTPUT->set_env('sort_order', $_SESSION['sort_order']);
   
   if ($attrib['messageicon'])
     $OUTPUT->set_env('messageicon', $skin_path . $attrib['messageicon']);
@@ -378,22 +200,35 @@ function rcmail_message_list($attrib)
     $OUTPUT->set_env('flaggedicon', $skin_path . $attrib['flaggedicon']);
   if ($attrib['unflaggedicon'])
     $OUTPUT->set_env('unflaggedicon', $skin_path . $attrib['unflaggedicon']);
+  if ($attrib['unreadchildrenicon'])
+    $OUTPUT->set_env('unreadchildrenicon', $skin_path . $attrib['unreadchildrenicon']);
   
-  $OUTPUT->set_env('messages', $a_js_message_arr);
+  $OUTPUT->set_env('messages', array());
   $OUTPUT->set_env('coltypes', $a_show_cols);
   
+  if (!$message_count)
+    $OUTPUT->show_message('nomessagesfound', 'notice');
+  
   $OUTPUT->include_script('list.js');
   
-  return $out;
-  }
+  $thead = '';
+  foreach (rcmail_message_list_head($attrib, $a_show_cols) as $cell)
+    $thead .= html::tag('td', array('class' => $cell['className'], 'id' => $cell['id']), $cell['html']);
+  
+  return html::tag('table',
+    $attrib,
+    html::tag('thead', null, html::tag('tr', null, $thead)) .
+      html::tag('tbody', null, ''),
+    array('style', 'class', 'id', 'cellpadding', 'cellspacing', 'border', 'summary'));
+}
 
 
 /**
  * return javascript commands to add rows to the message list
  * or to replace the whole list (IE only)
  */
-function rcmail_js_message_list($a_headers, $insert_top=FALSE, $replace=TRUE)
-  {
+function rcmail_js_message_list($a_headers, $insert_top=FALSE, $replace=TRUE, $head_replace=FALSE)
+{
   global $CONFIG, $IMAP, $OUTPUT;
 
   if (empty($_SESSION['list_columns']))
@@ -409,9 +244,12 @@ function rcmail_js_message_list($a_headers, $insert_top=FALSE, $replace=TRUE)
       && (($f = array_search('from', $a_show_cols)) !== false) && array_search('to', $a_show_cols) === false)
     $a_show_cols[$f] = 'to';
 
-  $browser = new rcube_browser;
+  $thead = $head_replace ? rcmail_message_list_head($_SESSION['list_attrib'], $a_show_cols) : NULL;
+  
+  $OUTPUT->command('set_message_coltypes', $a_show_cols, $thead);
 
-  $OUTPUT->command('set_message_coltypes', $a_show_cols);
+  if (empty($a_headers))
+    return;
 
   // remove 'attachment' and 'flag' columns, we don't need them here
   if(($key = array_search('attachment', $a_show_cols)) !== FALSE)
@@ -419,7 +257,7 @@ function rcmail_js_message_list($a_headers, $insert_top=FALSE, $replace=TRUE)
   if(($key = array_search('flag', $a_show_cols)) !== FALSE)
     unset($a_show_cols[$key]);
 
-  if ($browser->ie && $replace)
+  if ($OUTPUT->browser->ie && $replace)
     $OUTPUT->command('offline_message_list', true);
 
   // loop through message headers
@@ -440,10 +278,9 @@ function rcmail_js_message_list($a_headers, $insert_top=FALSE, $replace=TRUE)
         $cont = Q(rcmail_address_string($header->$col, 3), 'show');
       else if ($col=='subject')
         {
-	$cont = abbreviate_string(trim($IMAP->decode_header($header->$col)), 160);
+        $cont = abbreviate_string(trim($IMAP->decode_header($header->$col)), 160);
         if (!$cont) $cont = rcube_label('nosubject');
-	$cont = Q($cont);
-	$a_msg_cols['mbox'] = $mbox;
+        $cont = Q($cont);
         }
       else if ($col=='size')
         $cont = show_bytes($header->$col);
@@ -455,6 +292,14 @@ function rcmail_js_message_list($a_headers, $insert_top=FALSE, $replace=TRUE)
       $a_msg_cols[$col] = $cont;
       }
 
+    if ($header->depth)
+      $a_msg_flags['depth'] = $header->depth;
+    if ($header->parent_uid)
+      $a_msg_flags['parent_uid'] = $header->parent_uid;
+    if ($header->has_children)
+      $a_msg_flags['has_children'] = $header->has_children;
+    if ($header->unread_children)
+      $a_msg_flags['unread_children'] = $header->unread_children;
     if ($header->deleted)
       $a_msg_flags['deleted'] = 1;
     if (!$header->seen)
@@ -465,12 +310,14 @@ function rcmail_js_message_list($a_headers, $insert_top=FALSE, $replace=TRUE)
       $a_msg_flags['forwarded'] = 1;
     if ($header->flagged)
       $a_msg_flags['flagged'] = 1;
-      
+    if(preg_match("/multipart\/m/i", $header->ctype))
+      $a_msg_flags['attachment'] = 1;
+    $a_msg_flags['mbox'] = $mbox;
+
     $OUTPUT->command('add_message_row',
       $header->uid,
       $a_msg_cols,
       $a_msg_flags,
-      preg_match("/multipart\/m/i", $header->ctype),
       $insert_top);
     }
 
@@ -479,6 +326,61 @@ function rcmail_js_message_list($a_headers, $insert_top=FALSE, $replace=TRUE)
   }
 
 
+/*
+ * Creates <THEAD> for message list table
+ */
+function rcmail_message_list_head($attrib, $a_show_cols)
+{
+  global $CONFIG;
+
+  $skin_path = $_SESSION['skin_path'];
+  $image_tag = html::img(array('src' => "%s%s", 'alt' => "%s"));
+
+  // check to see if we have some settings for sorting
+  $sort_col   = $_SESSION['sort_col'];
+  $sort_order = $_SESSION['sort_order'];
+
+  // define sortable columns
+  $a_sort_cols = array('subject', 'date', 'from', 'to', 'size', 'cc');
+  
+  if (!empty($attrib['optionsmenuicon']))
+    $list_menu = html::a(
+      array('href' => '#', 'onclick' => 'return '.JS_OBJECT_NAME.".command('menu-open', 'messagelistmenu')"),
+      html::img(array('src' => $skin_path . $attrib['optionsmenuicon'], 'id' => 'listmenulink', 'title' => rcube_label('listoptions')))
+    );
+  else
+    $list_menu = '';
+
+  $cells = array(array('className' => 'threads', 'html' => $list_menu));
+
+  foreach ($a_show_cols as $col) {
+    // get column name
+    switch ($col) {
+      case 'flag':
+        $col_name = sprintf($image_tag, $skin_path, $attrib['unflaggedicon'], '');
+        break;
+      case 'attachment':
+        $col_name = sprintf($image_tag, $skin_path, $attrib['attachmenticon'], '');
+        break;
+      default:
+        $col_name = Q(rcube_label($col));
+    }
+
+    // make sort links
+    if (in_array($col, $a_sort_cols))
+      $col_name = html::a(array('href'=>"./#sort", 'onclick' => 'return '.JS_OBJECT_NAME.".command('sort','".$col."',this)", 'title' => rcube_label('sortby')), $col_name);
+
+    $sort_class = $col == $sort_col ? " sorted$sort_order" : '';
+    $class_name = $col == 'attachment' ? 'icon' : $col.$sort_class;
+
+    // put it all together
+    $cells[] = array('className' => $class_name, 'id' => "rcm$col", 'html' => $col_name);
+  }
+
+  return $cells;
+}
+
+
 /**
  * return an HTML iframe for loading mail content
  */
@@ -513,7 +415,7 @@ function rcmail_messagecount_display($attrib)
 
 function rcmail_quota_display($attrib)
   {
-  global $OUTPUT, $COMM_PATH;
+  global $OUTPUT;
 
   if (!$attrib['id'])
     $attrib['id'] = 'rcmquotadisplay';
@@ -582,23 +484,23 @@ function rcmail_get_messagecount_text($count=NULL, $page=NULL)
   if (isset($MESSAGE->index))
     {
     return rcube_label(array('name' => 'messagenrof',
-                             'vars' => array('nr'  => $MESSAGE->index+1,
-                                             'count' => $count!==NULL ? $count : $IMAP->messagecount())));
+        'vars' => array('nr'  => $MESSAGE->index+1,
+        'count' => $count!==NULL ? $count : $IMAP->messagecount(NULL, 'ALL')))); // Only messages, no threads here
     }
 
   if ($page===NULL)
     $page = $IMAP->list_page;
     
   $start_msg = ($page-1) * $IMAP->page_size + 1;
-  $max = $count!==NULL ? $count : $IMAP->messagecount();
+  $max = $count!==NULL ? $count : $IMAP->messagecount(NULL, $IMAP->threading ? 'THREADS' : 'ALL');
 
   if ($max==0)
     $out = rcube_label('mailboxempty');
   else
-    $out = rcube_label(array('name' => 'messagesfromto',
-                              'vars' => array('from'  => $start_msg,
-                                              'to'    => min($max, $start_msg + $IMAP->page_size - 1),
-                                              'count' => $max)));
+    $out = rcube_label(array('name' => $IMAP->threading ? 'threadsfromto' : 'messagesfromto',
+            'vars' => array('from'  => $start_msg,
+            'to'    => min($max, $start_msg + $IMAP->page_size - 1),
+            'count' => $max)));
 
   return Q($out);
   }
diff --git a/program/steps/mail/list.inc b/program/steps/mail/list.inc
index cd1a3142d..89d127cdc 100644
--- a/program/steps/mail/list.inc
+++ b/program/steps/mail/list.inc
@@ -33,8 +33,6 @@ if ($sort = get_input_value('_sort', RCUBE_INPUT_GET))
   $save_arr = array();
   $_SESSION['sort_col'] = $save_arr['message_sort_col'] = $sort_col;
   $_SESSION['sort_order'] = $save_arr['message_sort_order'] = $sort_order;
-  
-  $RCMAIL->user->save_prefs($save_arr);
 }
 else
 {
@@ -43,6 +41,16 @@ else
   $sort_order = isset($_SESSION['sort_order']) ? $_SESSION['sort_order'] : $CONFIG['message_sort_order'];
 }
 
+// is there a set of columns for this request?
+if ($cols = get_input_value('_cols', RCUBE_INPUT_GET))
+{
+  $save_arr = array();
+  $_SESSION['list_columns'] = $save_arr['list_cols'] = explode(',', $cols);
+}
+
+if ($save_arr)  
+  $RCMAIL->user->save_prefs($save_arr);
+
 $mbox_name = $IMAP->get_mailbox_name();
 
 // initialize searching result if search_filter is used
@@ -55,9 +63,13 @@ if ($_SESSION['search_filter'] && $_SESSION['search_filter'] != 'ALL')
 }
 
 // fetch message headers
-if ($count = $IMAP->messagecount($mbox_name, 'ALL', !empty($_REQUEST['_refresh'])))
+if ($count = $IMAP->messagecount($mbox_name, $IMAP->threading ? 'THREADS' : 'ALL', !empty($_REQUEST['_refresh'])))
   $a_headers = $IMAP->list_headers($mbox_name, NULL, $sort_col, $sort_order);
 
+// update search set (possible change of threading mode)
+if (!empty($_REQUEST['_search']) && isset($_SESSION['search'][$_REQUEST['_search']]))
+  $_SESSION['search'][$_REQUEST['_search']] = $IMAP->get_search_set();
+
 // update mailboxlist
 rcmail_send_unread_count($mbox_name, !empty($_REQUEST['_refresh']));
 
@@ -65,13 +77,14 @@ rcmail_send_unread_count($mbox_name, !empty($_REQUEST['_refresh']));
 $pages = ceil($count/$IMAP->page_size);
 $OUTPUT->set_env('messagecount', $count);
 $OUTPUT->set_env('pagecount', $pages);
+$OUTPUT->set_env('threading', (bool) $IMAP->threading);
 $OUTPUT->command('set_rowcount', rcmail_get_messagecount_text($count));
 $OUTPUT->command('set_mailboxname', rcmail_get_mailbox_name_text());
 
 // add message rows
+rcmail_js_message_list($a_headers, FALSE, TRUE, (bool) $cols);
 if (isset($a_headers) && count($a_headers))
 {
-  rcmail_js_message_list($a_headers);
   if ($search_request)
     $OUTPUT->show_message('searchsuccessful', 'confirmation', array('nr' => $count));
 }
diff --git a/program/steps/mail/mark.inc b/program/steps/mail/mark.inc
index 3e0ee9ecb..c37a6e47c 100644
--- a/program/steps/mail/mark.inc
+++ b/program/steps/mail/mark.inc
@@ -36,7 +36,7 @@ if (($uids = get_input_value('_uid', RCUBE_INPUT_POST)) && ($flag = get_input_va
 
   if ($flag == 'DELETED' && $CONFIG['skip_deleted'] && $_POST['_from'] != 'show') {
     // count messages before changing anything
-    $old_count = $IMAP->messagecount();
+    $old_count = $IMAP->messagecount(NULL, $IMAP->threading ? 'THREADS' : 'ALL');
     $old_pages = ceil($old_count / $IMAP->page_size);
     $count = sizeof(explode(',', $uids));
   }
@@ -75,7 +75,7 @@ if (($uids = get_input_value('_uid', RCUBE_INPUT_POST)) && ($flag = get_input_va
         $_SESSION['search'][$search_request] = $IMAP->refresh_search();
       }
 
-      $msg_count      = $IMAP->messagecount();
+      $msg_count      = $IMAP->messagecount(NULL, $IMAP->threading ? 'THREADS' : 'ALL');
       $pages          = ceil($msg_count / $IMAP->page_size);
       $nextpage_count = $old_count - $IMAP->page_size * $IMAP->list_page;
       $remaining      = $msg_count - $IMAP->page_size * ($IMAP->list_page - 1);
@@ -103,8 +103,11 @@ if (($uids = get_input_value('_uid', RCUBE_INPUT_POST)) && ($flag = get_input_va
       }
       $OUTPUT->command('set_rowcount', rcmail_get_messagecount_text($msg_count));
 
+      if ($IMAP->threading)
+	$count = get_input_value('_count', RCUBE_INPUT_POST);
+
       // add new rows from next page (if any)
-      if (($jump_back || $nextpage_count > 0)) {
+      if ($count && ($jump_back || $nextpage_count > 0)) {
         $sort_col   = isset($_SESSION['sort_col'])   ? $_SESSION['sort_col']   : $CONFIG['message_sort_col'];
         $sort_order = isset($_SESSION['sort_order']) ? $_SESSION['sort_order'] : $CONFIG['message_sort_order'];
   
diff --git a/program/steps/mail/move_del.inc b/program/steps/mail/move_del.inc
index b8bd16557..f884a781e 100644
--- a/program/steps/mail/move_del.inc
+++ b/program/steps/mail/move_del.inc
@@ -24,7 +24,7 @@ if (!$OUTPUT->ajax_call)
   return;
 
 // count messages before changing anything
-$old_count = $IMAP->messagecount();
+$old_count = $IMAP->messagecount(NULL, $IMAP->threading ? 'THREADS' : 'ALL');
 $old_pages = ceil($old_count / $IMAP->page_size);
 
 // move messages
@@ -50,6 +50,7 @@ if ($RCMAIL->action=='moveto' && !empty($_POST['_uid']) && !empty($_POST['_targe
 else if ($RCMAIL->action=='delete' && !empty($_POST['_uid'])) {
     $count = sizeof(explode(',', ($uids = get_input_value('_uid', RCUBE_INPUT_POST))));
     $mbox = get_input_value('_mbox', RCUBE_INPUT_POST);
+
     $del = $IMAP->delete_message($uids, $mbox);
   
     if (!$del) {
@@ -82,7 +83,7 @@ if ($_POST['_from'] == 'show')
 }
 else
 {
-  $msg_count      = $IMAP->messagecount();
+  $msg_count      = $IMAP->messagecount(NULL, $IMAP->threading ? 'THREADS' : 'ALL');
   $pages          = ceil($msg_count / $IMAP->page_size);
   $nextpage_count = $old_count - $IMAP->page_size * $IMAP->list_page;
   $remaining      = $msg_count - $IMAP->page_size * ($IMAP->list_page - 1);
@@ -116,8 +117,11 @@ else
   $OUTPUT->command('set_quota', rcmail_quota_content());
   $OUTPUT->command('set_rowcount', rcmail_get_messagecount_text($msg_count));
 
+  if ($IMAP->threading)
+    $count = get_input_value('_count', RCUBE_INPUT_POST);
+
   // add new rows from next page (if any)
-  if ($addrows && ($jump_back || $nextpage_count > 0)) {
+  if ($addrows && $count && ($jump_back || $nextpage_count > 0)) {
     $sort_col   = isset($_SESSION['sort_col'])   ? $_SESSION['sort_col']   : $CONFIG['message_sort_col'];
     $sort_order = isset($_SESSION['sort_order']) ? $_SESSION['sort_order'] : $CONFIG['message_sort_order'];
 
diff --git a/program/steps/mail/search.inc b/program/steps/mail/search.inc
index 54c765047..52469952a 100644
--- a/program/steps/mail/search.inc
+++ b/program/steps/mail/search.inc
@@ -104,7 +104,7 @@ if ($search_str)
 
 // Get the headers
 $result_h = $IMAP->list_headers($mbox, 1, $_SESSION['sort_col'], $_SESSION['sort_order']);
-$count = $IMAP->messagecount();
+$count = $IMAP->messagecount(NULL, $IMAP->threading ? 'THREADS' : 'ALL');
 
 // save search results in session
 if (!is_array($_SESSION['search']))
@@ -120,7 +120,7 @@ if (!empty($result_h))
 {
   rcmail_js_message_list($result_h);
   if ($search_str)
-    $OUTPUT->show_message('searchsuccessful', 'confirmation', array('nr' => $count));
+    $OUTPUT->show_message('searchsuccessful', 'confirmation', array('nr' => $IMAP->messagecount(NULL, 'ALL')));
 }
 else
 {
diff --git a/program/steps/mail/show.inc b/program/steps/mail/show.inc
index 33e87d5bc..02e1f4824 100644
--- a/program/steps/mail/show.inc
+++ b/program/steps/mail/show.inc
@@ -104,7 +104,7 @@ if ($_GET['_uid']) {
     $next = $prev = $first = $last = -1;
 
     if ($_SESSION['sort_col'] == 'date' && $_SESSION['sort_order'] != 'DESC'
-        && empty($_REQUEST['_search']) && !$IMAP->skip_deleted)
+        && empty($_REQUEST['_search']) && !$CONFIG['skip_deleted'] && !$IMAP->threading)
       {
       // this assumes that we are sorted by date_DESC
       $cnt = $IMAP->messagecount();
@@ -142,7 +142,7 @@ if ($_GET['_uid']) {
 
   if (!$MESSAGE->headers->seen)
     $RCMAIL->plugins->exec_hook('message_read', array('uid' => $MESSAGE->uid,
-      'mailbox' => $IMAP->mailbox, 'message' => $MESSAGE));
+      'mailbox' => $mbox_name, 'message' => $MESSAGE));
 }
 
 
diff --git a/program/steps/mail/viewsource.inc b/program/steps/mail/viewsource.inc
index 17e382456..2e2228ab6 100644
--- a/program/steps/mail/viewsource.inc
+++ b/program/steps/mail/viewsource.inc
@@ -25,7 +25,7 @@ ob_end_clean();
 if ($uid = get_input_value('_uid', RCUBE_INPUT_GET))
 {
   $headers = $IMAP->get_headers($uid);
-  $charset = $headers->charset ? $headers->charset : $IMAP->default_charset;
+  $charset = $headers->charset ? $headers->charset : $CONFIG['default_charset'];
   header("Content-Type: text/plain; charset={$charset}");
 
   if (!empty($_GET['_save'])) {
diff --git a/program/steps/settings/func.inc b/program/steps/settings/func.inc
index 44225c715..421fb37bf 100644
--- a/program/steps/settings/func.inc
+++ b/program/steps/settings/func.inc
@@ -248,17 +248,6 @@ function rcmail_user_prefs($current=null)
       );
     }
 
-    // Show checkbox for toggling 'index_sort' 
-    if (!isset($no_override['index_sort'])) {
-      $field_id = 'rcmfd_indexsort';
-      $input_indexsort = new html_checkbox(array('name' => '_index_sort', 'id' => $field_id, 'value' => 1));
-
-      $blocks['list']['options']['index_sort'] = array(
-        'title' => html::label($field_id, Q(rcube_label('indexsort'))),
-        'content' => $input_indexsort->show($config['index_sort']?1:0),
-      );
-    }
-
     // show drop-down for available skins
     if (!isset($no_override['skin'])) {
       $skins = rcmail_get_skins();
@@ -311,6 +300,19 @@ function rcmail_user_prefs($current=null)
       );
     }
 
+    if (!isset($no_override['autoexpand_threads'])) {
+      $field_id = 'rcmfd_autoexpand_threads';
+      $select_autoexpand_threads = new html_select(array('name' => '_autoexpand_threads', 'id' => $field_id));
+      $select_autoexpand_threads->add(rcube_label('never'), 0);
+      $select_autoexpand_threads->add(rcube_label('do_expand'), 1);
+      $select_autoexpand_threads->add(rcube_label('expand_only_unread'), 2);
+      
+      $blocks['main']['options']['autoexpand_threads'] = array(
+	'title' => html::label($field_id, Q(rcube_label('autoexpand_threads'))),
+	'content' => $select_autoexpand_threads->show($config['autoexpand_threads']),
+      );
+    }
+
     if (!isset($no_override['focus_on_new_message'])) {
       $field_id = 'rcmfd_focus_on_new_message';
       $input_focus_on_new_message = new html_checkbox(array('name' => '_focus_on_new_message', 'id' => $field_id, 'value' => 1));
diff --git a/program/steps/settings/manage_folders.inc b/program/steps/settings/manage_folders.inc
index 06fee7a87..fa5a4db70 100644
--- a/program/steps/settings/manage_folders.inc
+++ b/program/steps/settings/manage_folders.inc
@@ -38,6 +38,20 @@ else if ($RCMAIL->action=='unsubscribe')
     $IMAP->unsubscribe(array($mbox));
   }
 
+// enable threading for one or more mailboxes
+else if ($RCMAIL->action=='enable-threading')
+  {
+  if ($mbox = get_input_value('_mbox', RCUBE_INPUT_POST, false, 'UTF7-IMAP'))
+    rcube_set_threading($mbox, true);
+  }
+
+// enable threading for one or more mailboxes
+else if ($RCMAIL->action=='disable-threading')
+  {
+  if ($mbox = get_input_value('_mbox', RCUBE_INPUT_POST, false, 'UTF7-IMAP'))
+    rcube_set_threading($mbox, false);
+  }
+
 // create a new mailbox
 else if ($RCMAIL->action=='create-folder')
   {
@@ -79,6 +93,24 @@ else if ($RCMAIL->action=='rename-folder')
     $rename = $IMAP->rename_mailbox($oldname, $name);
     }
 
+  // update per-folder options for modified folder and its subfolders
+  if ($rename) {
+    $a_threaded = $RCMAIL->config->get('message_threading', array()); 
+    $delimiter = $IMAP->get_hierarchy_delimiter();
+    $oldprefix = '/^' . preg_quote($oldname . $delimiter, '/') . '/';
+    foreach ($a_threaded as $key => $val)
+      if ($key == $oldname) {
+        unset($a_threaded[$key]);
+	$a_threaded[$name] = true;
+        }
+      else if (preg_match($oldprefix, $key)) {
+        unset($a_threaded[$key]);
+	$a_threaded[preg_replace($oldprefix, $name.$delimiter, $key)] = true;      
+      }
+      
+    $RCMAIL->user->save_prefs(array('message_threading' => $a_threaded));
+    }
+
   if ($rename && $OUTPUT->ajax_call)
     {
     $folderlist = $IMAP->list_unsubscribed();
@@ -159,7 +191,11 @@ if ($OUTPUT->ajax_call)
 // build table with all folders listed by server
 function rcube_subscription_form($attrib)
   {
-  global $IMAP, $CONFIG, $OUTPUT;
+  global $RCMAIL, $IMAP, $CONFIG, $OUTPUT;
+
+  $threading_supported = $IMAP->get_capability('thread=references')
+    || $IMAP->get_capability('thread=orderedsubject')
+    || $IMAP->get_capability('thread=refs');
 
   list($form_start, $form_end) = get_form_tags($attrib, 'folders');
   unset($attrib['form']);
@@ -173,15 +209,17 @@ function rcube_subscription_form($attrib)
   $table->add_header('name', rcube_label('foldername'));
   $table->add_header('msgcount', rcube_label('messagecount'));
   $table->add_header('subscribed', rcube_label('subscribed'));
+  if ($threading_supported)
+    $table->add_header('threaded', rcube_label('threaded'));
   $table->add_header('rename', '&nbsp;');
   $table->add_header('delete', '&nbsp;');
 
-
   // get folders from server
   $IMAP->clear_cache('mailboxes');
 
   $a_unsubscribed = $IMAP->list_unsubscribed();
   $a_subscribed = $IMAP->list_mailboxes();
+  $a_threaded = $a_threaded_copy = $RCMAIL->config->get('message_threading', array()); 
   $delimiter = $IMAP->get_hierarchy_delimiter();
   $a_js_folders = $seen_folders = $list_folders = array();
 
@@ -203,14 +241,28 @@ function rcube_subscription_form($attrib)
       }
     }
     
+    unset($a_threaded_copy[$folder]);
+    
     $list_folders[] = array('id' => $folder, 'name' => $name, 'level' => $level);
     $seen[$folder]++;
   }
 
+  // remove 'message_threading' option for not existing folders
+  if ($a_threaded_copy) {
+    foreach ($a_threaded_copy as $key => $val)
+      unset($a_threaded[$key]);
+    unset($a_threaded_copy);
+    $RCMAIL->user->save_prefs(array('message_threading' => $a_threaded));
+  }
+
   $checkbox_subscribe = new html_checkbox(array(
     'name' => '_subscribed[]',
     'onclick' => JS_OBJECT_NAME.".command(this.checked?'subscribe':'unsubscribe',this.value)",
   ));
+  $checkbox_threaded = new html_checkbox(array(
+    'name' => '_threaded[]',
+    'onclick' => JS_OBJECT_NAME.".command(this.checked?'enable-threading':'disable-threading',this.value)",
+  ));
   
   if (!empty($attrib['deleteicon']))
     $del_button = html::img(array('src' => $CONFIG['skin_path'] . $attrib['deleteicon'], 'alt' => rcube_label('delete')));
@@ -226,6 +278,7 @@ function rcube_subscription_form($attrib)
   foreach ($list_folders as $i => $folder) {
     $idx = $i + 1;
     $subscribed = in_array($folder['id'], $a_subscribed);
+    $threaded = $a_threaded[$folder['id']];
     $protected = ($CONFIG['protect_default_folders'] == true && in_array($folder['id'], $CONFIG['default_imap_folders']));
     $classes = array($i%2 ? 'even' : 'odd');
     $folder_js = JQ($folder['id']);
@@ -238,9 +291,13 @@ function rcube_subscription_form($attrib)
     $table->add_row(array('id' => 'rcmrow'.$idx, 'class' => join(' ', $classes)));
     
     $table->add('name', Q($display_folder));
-    $table->add('msgcount', ($folder['virtual'] ? '' : $IMAP->messagecount($folder['id'])));
+    $table->add('msgcount', ($folder['virtual'] ? '' : $IMAP->messagecount($folder['id']))); // XXX: Use THREADS or ALL?
     $table->add('subscribed', ($protected || $folder['virtual']) ? ($subscribed ? '&nbsp;&#x2022;' : '&nbsp;') :
         $checkbox_subscribe->show(($subscribed ? $folder_utf8 : ''), array('value' => $folder_utf8)));
+    if ($IMAP->get_capability('thread=references')) {
+      $table->add('threaded',
+                  $checkbox_threaded->show(($threaded ? $folder_utf8 : ''), array('value' => $folder_utf8)));
+    }
     
     // add rename and delete buttons
     if (!$protected && !$folder['virtual']) {
@@ -335,6 +392,27 @@ function rcube_rename_folder_form($attrib)
   return $out;
   }
 
+
+// (un)set 'threading' for selected folder
+function rcube_set_threading($mbox, $state=true)
+  {
+  global $RCMAIL;
+  $mbox = (array)$mbox;
+  $a_prefs = (array)$RCMAIL->config->get('message_threading');
+
+  if ($state) {
+    foreach ($mbox as $box)
+      $a_prefs[$box] = true;
+    }
+  else {
+    foreach ($mbox as $box)
+      unset($a_prefs[$box]);
+    }
+
+  $RCMAIL->user->save_prefs(array('message_threading' => $a_prefs));
+  }
+
+
 $OUTPUT->set_pagetitle(rcube_label('folders'));
 $OUTPUT->include_script('list.js');
 
diff --git a/program/steps/settings/save_prefs.inc b/program/steps/settings/save_prefs.inc
index eeb64034c..4eebef291 100644
--- a/program/steps/settings/save_prefs.inc
+++ b/program/steps/settings/save_prefs.inc
@@ -32,7 +32,6 @@ switch ($CURR_SECTION)
       'timezone'     => isset($_POST['_timezone']) ? (is_numeric($_POST['_timezone']) ? floatval($_POST['_timezone']) : get_input_value('_timezone', RCUBE_INPUT_POST)) : $CONFIG['timezone'],
       'dst_active'   => isset($_POST['_dst_active']) ? TRUE : FALSE,
       'pagesize'     => is_numeric($_POST['_pagesize']) ? max(2, intval($_POST['_pagesize'])) : $CONFIG['pagesize'],
-      'index_sort'   => isset($_POST['_index_sort']) ? TRUE : FALSE,
       'prettydate'   => isset($_POST['_pretty_date']) ? TRUE : FALSE,
       'skin' 	     => isset($_POST['_skin']) ? get_input_value('_skin', RCUBE_INPUT_POST) : $CONFIG['skin'],
     );
@@ -42,6 +41,7 @@ switch ($CURR_SECTION)
     $a_user_prefs = array(
       'focus_on_new_message' => isset($_POST['_focus_on_new_message']) ? TRUE : FALSE,
       'preview_pane' 	     => isset($_POST['_preview_pane']) ? TRUE : FALSE,
+      'autoexpand_threads'   => isset($_POST['_autoexpand_threads']) ? intval($_POST['_autoexpand_threads']) : 0,
       'mdn_requests'         => isset($_POST['_mdn_requests']) ? intval($_POST['_mdn_requests']) : 0,
       'keep_alive'           => isset($_POST['_keep_alive']) ? intval($_POST['_keep_alive'])*60 : $CONFIG['keep_alive'],
       'check_all_folders'    => isset($_POST['_check_all_folders']) ? TRUE : FALSE,